1. Field of the Invention
The present invention relates to a coating film removing apparatus for removing a coating film formed at an end portion of the coating film formed on a substrate.
2. Description of the Related Art
In recent years, for example, in a manufacturing process of a semiconductor device, a semiconductor wafer (hereinafter, referred to as a “wafer”) is progressively increased in diameter. Further, in a specific step such as mounting, the wafer is required to be thinned. For example, a thin wafer with a large diameter is transferred or subjected to polishing processing as it is, the wafer may be warped or broken. Therefore, for example, to reinforce the wafer, a wafer is bonded to a wafer being a support substrate or a glass substrate.
The bonding of the wafer with the support substrate is performed by using, for example, a bonder and an adhesive intervening between the wafer and the support substrate. The bonder has, for example, a first holding member that holds the wafer, a second holding member that holds the support substrate, a heating mechanism that heats the adhesive arranged between the wafer and the support substrate, and a moving mechanism that moves at least the first holding member or the second holding member in the vertical direction. Further, in the bonder, the adhesive is supplied between the wafer and the support substrate and heated, and then the wafer and the support substrate are pressed to be bonded together (Japanese Patent Application Laid-open No. 2008-182016).
When the wafer and the support substrate are pressed to be bonded together using the apparatus described in Japanese Patent Application Laid-open No. 2008-182016, the adhesive protrudes from between the wafer and the support substrate. Accordingly, removal of the adhesive at a wafer end surface portion is required. As a method of removing the end surface portion of the coating film formed of a coating solution applied on the wafer such as the adhesive, there is a known technique of removing the coating film (processing film) at the wafer end surface portion by discharging a solvent (removing solution) to the wafer end surface portion while rotating the wafer after the application of the coating solution to the wafer (Japanese Patent Application Laid-open No. 2003-100704).
However, it has been difficult to perform fine processing by the technique described in the Japanese Patent Application Laid-open No. 2003-100704 due to the influence of the kind and the film thickness and so on of the coating solution to be applied on the wafer. Besides, there are disadvantages that the solvent discharged to the wafer end surface portion splashes back and adheres to a wafer central portion and that it takes time to perform processing because the coating solution is applied to the wafer and then the coating film at the wafer end surface portion is removed as it is without moving the wafer, namely, the application and the end surface removal of the coating solution are performed in the same apparatus.